JPH09161327A - Optical card - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide an optical card which may be subjected to good embossing similar to the embossing of ordinary plastic cards. SOLUTION: This optical card is constituted by forming an optical recording layer 2 on one surface of a light transparent pattern layer 1, laminating a card base material 4 via an adhesive layer 3 on the front surface of the optical recording layer 2 and laminating a transparent protective layer 5 and a surface hardening layer 6 on the surface on the side opposite to the side provided with the optical recording layer 2 of the pattern layer 1. The card base material 4 which has tensile strength of >=500kgf/cm<2> and breaking elongation of <=20% is used. Talc is added to the resin constituting the card base material 4 for this purpose.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an optical card used for credit cards, cash cards, medical cards and the like.

[0002]

Conventionally, as a card type recording medium, an optical card having a storage capacity larger than that of a magnetic card or an IC card has been developed. This optical card generally records information by changing the optical characteristics such as transmittance and reflectance by volatilizing or deforming a part of the optical recording layer using a light beam such as a laser beam. . By the way, magnetic cards and IC cards are generally used in which card information such as personal name and registration number is made into embossed characters, but similar embossing can be applied to optical cards. It has been demanded. However, an optical card usually has a structure in which a surface hardened layer, a transparent protective layer, an optical recording layer, and a card substrate are laminated. Therefore, when embossed, the card is warped or the transparent protective layer is cracked. Has occurred,
Recording and reproduction may be difficult.

Therefore, the present inventor has previously proposed that the embossing is possible by defining the hardness of the adhesive used for laminating the card substrate on the optical recording layer side of the transparent protective layer. That is, by using an adhesive having a high breaking strength and a small breaking elongation as the adhesive, embossing can be performed without causing a large warp in the card (see Japanese Patent Laid-Open No. 7-257079). However, in the case of this optical card, although embossing of two lines is possible, good embossing is impossible with three lines. Further, when the embossed area is in the center of the card, good embossing was impossible even with two lines.

The present invention has been made in view of the above circumstances, and an object of the present invention is to provide an optical card which can be embossed as well as a normal plastic card.

[0005]

In the layer structure of an optical card, the outermost surface hardened layer is very thin from the entire card and does not contribute to the quality of embossing. The transparent protective layer is specified as 400 ± 40 μm in the standard and has a dominant influence on embossing. Polycarbonate (PC) is an excellent material for the transparent protective layer.
Acrylic cracks during embossing. The tensile strength of PC is 640 kgf / cm ² , but the breaking elongation is 1
Since it is 00%, there is a drawback that it is difficult to plastically deform.
Further, the adhesive layer is also related to the quality of embossing. Further, the material of the card base material is also related to the quality of embossing. PVC is excellent in embossing suitability, but in the case of optical cards, even if ordinary PVC is used as the card base material, a transparent protective layer (P
The influence of C) is dominant. Therefore, it is necessary to obtain the embossing suitability of the entire card by giving the card base material further embossing suitability.

As a result of earnest research based on the above, it was found that the embossing suitability of the optical card is greatly related to the tensile strength and the breaking elongation of the card base material, and the present invention has been completed. . The present invention provides an optical card in which a surface-hardened layer, a transparent protective layer, an optical recording layer, and a card substrate are laminated in this order, and the card substrate has a tensile strength of 500 kgf / cm ² or more and a breaking elongation. Is 20
%.

It has been found that talc is effective among the many additives for obtaining the physical properties. The amount of talc should be at most 30%. If it exceeds 30%, the PVC sheeting will not be performed well. 1
The effect of 0 to 20% on the embossing suitability and the mass productivity are excellent.

The thicker the card substrate, the better. That is, the embossability is improved by increasing the composition ratio of PVC. The thickness of the card is ISO standard up to 840 μm,
It is up to 800 μm according to the JIS standard. According to the standard, the transparent protective layer has a thickness of 400 ± 40 μm and the minimum thickness is 360 μm (including the surface-hardened layer), and the adhesive layer needs to have a minimum of 30 μm to function as an adhesive. Has a maximum thickness of 450 μm.

[0009]

1 is a perspective view showing an optical card as an example of the present invention, and FIG. 2 is a sectional view taken along line AA of FIG.

In this optical card C, an optical recording layer 2 constituting an optical recording portion is formed on one surface of a light-transmissive pattern layer 1,
A card substrate 4 is laminated on the surface of the optical recording layer 2 via an adhesive layer 3, and a transparent protective layer 5 and a surface hardened layer are provided on the surface of the pattern layer 1 opposite to the side on which the optical recording layer 2 is provided. 6 is laminated. In this optical card C, as the card substrate 4, an oversheet 4a made of transparent polyvinyl chloride and a core sheet 4 made of opalescent polyvinyl chloride
b, a three-layer structure in which an oversheet 4c made of transparent polyvinyl chloride is laminated is used, and printing layers 7a and 7c are provided on both surfaces of the core sheet 4b.

As a material used for the transparent protective layer 5, it is of course necessary that the birefringence be small, but if a low molecular weight material is used, cracking will occur due to the pressure during embossing, so a high molecular weight material that does not cause cracking will be used. You need to use one. Specifically, polycarbonate (PC), polymethylmethacrylate (PMMA), acrylonitrile-styrene copolymer (AS), cellulose propionate (C
P), cellulose acetate butyrate (CAB), polyvinyl chloride (PVC), polyester and the like can be used, and among these, polycarbonate (PC) having a molecular weight of 25,000 or more is suitable.

As the surface hardened layer 6 formed on the transparent protective layer 5, an acrylic UV curable hard coat agent is suitable. Other hard coat agents such as melamine-based and silicon-based agents may be used, but those having excellent temperature / humidity suitability, high hardness, and crack-free bending are preferably used.

The pattern layer 1 between the transparent protective layer 5 and the optical recording layer 2 is formed by the generally known 2P method, injection method,
It is formed on the transparent protective layer 5 by using a casting method or the like. At this time, when a pattern is formed by the 2P method, a UV-curable resin is used, and by the injection method and the casting method, the same transparent protective layer is used. In addition,
The injection method and the casting method eliminate the interface between the transparent protective layer 5 and the pattern layer 1.

As the optical recording layer 2 provided to cover the pattern layer 1, in addition to the commonly used metal-based optical recording materials such as tellurium-based and bismuth-based materials, dye-based optical recording materials such as phthalocyanine-based materials and naphthoquinone-based materials are used. Can be used. Also,
Not only the write-once type but also the ROM type may be used.

As the card substrate 4, polyvinyl chloride excellent in embossing suitability is used. The larger the thickness ratio of the polyvinyl chloride in the card form, the better the embossing suitability. The configuration used is 0.05 / 0.20 / 0.05 mm, 0.
05 / 0.24 / 0.05 mm, 0.05 / 0.26 /
0.05mm, 3 layers such as 0.05 / 0.30 / 0.05mm, 0.20 / 0.10mm, 0.24 / 0.10m
m, 0.26 / 0.10 mm, 0.30 / 0.10 mm
Etc. 2 layers, 0.30mm, 0.34mm, 0.36m
Any layer structure is possible, such as one layer of m and 0.40 mm. However, it is a necessary condition that both the laminated layer and the single layer have a thickness of 450 μm or less. Within this range, the larger the total thickness of PVC, the better the embossing suitability. It is preferable to set the thickness to about 400 μm. In addition, 0.10 mm, 0.05 m
m is transparent polyvinyl chloride, and 0.20 mm or more is opalescent polyvinyl chloride. Then, in order to increase the abrasion resistance of printing, it is preferable to perform printing on opal white polyvinyl chloride and heat-seal with transparent polyvinyl chloride in two or three layers.

As the adhesive forming the adhesive layer 3, conventionally known adhesives such as urethane-based, epoxy-based, acrylic-based, vinyl-based and amide-based adhesives can be used, but a sensitizing layer and a transparent protective layer described later are used. If it does not exist, it is directly adhered to the optical recording layer, so that it has good recording sensitivity and is suitable for temperature and humidity. Further, in the present invention, it is preferable to use those having excellent embossing suitability. Specifically, it is advisable to use a film made of an adhesive having a breaking strength of 50 kg / cm ² or more and a breaking elongation of 600% or less. The film thickness is preferably 5 to 100 μm, and more preferably 10 to 50 μm, which has adhesive force and does not cause delamination. The adhesive is formed on the card substrate side or the pattern layer side by a coating method such as gravure coating, spin coating, knife coating, silk screen, T-die coating, and miyabar coating, and the card and pattern are sandwiched by the optical recording layer. Laminate the layers together. A roll press, a flat press, a hot roll press, a hot flat press, or the like can be used for bonding.

When the recording sensitivity of the optical recording layer 2 is low,
A sensitizing layer is formed between the optical recording layer 2 and the adhesive layer 3,
It is not necessary if the recording sensitivity is sufficient. Although the adhesive layer 3 is in contact with the optical recording layer 2, an optical recording protective layer is provided in order to prevent the recording sensitivity of the optical recording portion from being deteriorated by the adhesive. When the sensitizing layer is provided, the optical recording protective layer is formed between the sensitizing layer and the adhesive layer 3, but it can also serve as the sensitizing layer. However, if a material that does not deteriorate the optical recording layer is selected, it is not necessary to provide this optical recording protective layer.

As shown in FIG. 1, this optical card C is embossed in a predetermined area (emboss area) other than the optical recording layer 2. In the figure, the embossing is provided so as to project to the surface hardened layer 6 side, but the embossing may be provided so as to project to the card base material 2 side. However,
In the case of tipping, that is, coloring by transferring a color to the embossed convex portion, it adheres to the polyvinyl chloride of the card base material 4, but does not adhere to the hard coat surface of the surface hardened layer 6, so that the card base material 2 side The appearance is better when the convex portions are formed. In order to improve the suitability for such embossing, the tensile strength of the polyvinyl chloride constituting the card substrate is 5
A material having a breaking elongation of 20% or less and a breaking strength of 00 kgf / cm ² or more is used.

The optical card of the present invention may be provided with an IC module and / or a magnetic tape in addition to the optical recording section and the embossed area. As an example, FIG.
The one shown in FIG. 4 has a magnetic tape 9 provided on the back side of the card, and the one shown in FIG. 4 has two magnetic tapes 9 provided on the back side of the card and an IC module 10 provided on the front side. Is.

[0020]

EXAMPLES Hereinafter, examples will be described together with comparative examples.

Example 1 First, a sheet-molded polycarbonate having a thickness of 0.4 mm (molecular weight 25000)
Hard coating agent (made by Toray, UH-
001) was applied to form a surface-hardened layer. Then, a guide track pattern was formed on the opposite surface by the 2P method, and TeOx was sputtered on the guide track pattern to form an optical recording layer. On the other hand, double-sided silk offset printing was performed on a core sheet of 0.26 mm opalescent vinyl chloride,
The two oversheets of transparent vinyl chloride of No. 3 were sandwiched and heat-bonded to prepare a three-layer card base material. A magnetic tape of 650 Oersted was formed on one surface of the oversheet. The opalescent vinyl chloride sheet and the transparent vinyl chloride sheet used here are sheets made of a resin obtained by adding 20% of talc to polyvinyl chloride. Then, an optical card sample was prepared by adhering the card base material and the polycarbonate using an adhesive (Kanebo NSC, bond master “170-7310” (reactive HM)). Specifically, an adhesive is applied to the card substrate using a T-die,
After bonding with polycarbonate with a heat laminator,
The card was sized by punching.

(Example 2) An optical card sample was prepared in the same manner as in Example 1 except that the card base material was changed to the following. That is, a card base material was used in which a 0.05 mm transparent vinyl chloride oversheet was laminated on one side of a 0.28 mm opalescent vinyl chloride core sheet. The opalescent vinyl chloride sheet and the transparent vinyl chloride sheet used here are sheets made of polyvinyl chloride with 10% talc added.

(Example 3) An optical card sample was prepared in the same manner as in Example 1 except that the following card base material was used. That is, a card base material was used in which a 0.05 mm transparent vinyl chloride oversheet was laminated on both surfaces of a 0.30 mm milky vinyl chloride core sheet. The opalescent vinyl chloride sheet and the transparent vinyl chloride sheet used here are sheets made of polyvinyl chloride containing 30% talc.

Comparative Example 1 An optical card sample was prepared in the same manner as in Example 1 except that the opalescent vinyl chloride sheet and the transparent vinyl chloride sheet of the card substrate were replaced by the following. That is, a polyvinyl chloride sheet was used which was made of a resin obtained by adding 30% of mica to polyvinyl chloride.

(Comparative Example 2) An optical card sample was prepared in the same manner as in Example 1, except that the opalescent vinyl chloride sheet and the transparent vinyl chloride sheet of the card substrate were replaced by the following. That is, a vinyl chloride sheet was used in which a resin obtained by adding 30% of calcium carbonate to polyvinyl chloride was formed into a sheet.

(Comparative Example 3) An optical card sample was prepared in the same manner as in Example 1 except that the opalescent vinyl chloride sheet and the transparent vinyl chloride sheet of the card base material in Example 1 were replaced by a vinyl chloride sheet without additives.

An embossing device (Data Card Co., DC-
4600) was used to emboss two rows each. Then, the warp of the card after embossing was measured. Table 1 shows the results. The evaluation of the material of the card base material was carried out by the test method of the ASTM standard.

[0028]

[Table 1]

As shown in Table 1, the bending strength and bending elastic modulus of the card base material are not so closely related to the embossability. It can be seen that in order to improve the embossing suitability, the breaking elongation may be lowered without lowering the tensile strength. For that purpose, the addition of talc is effective. That is, when mica is added to polyvinyl chloride, the breaking elongation decreases, but the tensile strength also decreases. When calcium carbonate is added, the tensile strength is lowered, but the breaking elongation is not so lowered. However, adding talc does not reduce the tensile strength,
It is possible to reduce the breaking elongation. This is because the particle size of talc is large and the addition of talc facilitates plastic deformation.

For each of the above samples, an optical card R
/ W (manufactured by OMRON, 3B3H-DJ-01) writes 100 tracks of data, magnetic R / W (manufactured by Sankyo Seiki,
After 1000 passes with MCT-141), the data written in advance was read, and the data of 100 tracks was further written and read. All cards had an optical recording error rate of 1 × 10 ⁻⁴ or less, and no deterioration due to magnetic R / W transport scratches occurred. Also, the above sample was subjected to 10
After being left for 00 hours, the error rate remained at 1 × 10 ⁻⁴ or less and the stability with time was good.

[0031]

As described above, according to the present invention, an optical card having a surface-hardened layer, a transparent protective layer, an optical recording layer and a card substrate laminated in this order has a tensile strength of 500 kg.
By using a card base material having f / cm ² or more and a breaking elongation of 20% or less, good embossing can be performed on the card without causing a large warp like a normal plastic card.

[Brief description of the drawings]

FIG. 1 is a perspective view showing an example of an optical card.

FIG. 2 is a sectional view taken along line AA of FIG.

FIG. 3 is a perspective view showing an example of an optical card to which a magnetic tape is added.

FIG. 4 is a perspective view showing an example of an optical card to which two magnetic tapes and an IC module are added.

[Explanation of symbols]

 C Optical card 1 Pattern layer 2 Optical recording layer 3 Adhesive layer 4 Card base material 4a Oversheet 4b Core sheet 4c Oversheet 5 Transparent protective layer 6 Surface hardening layer 7a, 7c Printing layer 9 Magnetic tape 10 IC module

Claims (4)

[Claims] 1. An optical card comprising a surface-cured layer, a transparent protective layer, an optical recording layer, and a card substrate laminated in this order,
An optical card, wherein the card base material has a tensile strength of 500 kgf / cm ² or more and a breaking elongation of 20% or less. 2. The optical card according to claim 1, wherein the physical characteristics are achieved by adding talc to the resin forming the card base material. 3. The optical card according to claim 2, wherein the talc is contained in an amount of at most 30% with respect to the resin component of the card base material. 4. The optical card according to claim 1, wherein the card substrate has a thickness of 450 μm or less.